public class Test {
    public static int fei(int n){
        int a=1;
        int b=1;
        if(n==1||n==2){
            return 1;
        }
        return fei(n-1)+fei(n-2);
    }

    public static void main(String[] args) {
        System.out.println(fei(6));
    }
}
